Showing papers in "International Journal of Plasticity in 2018"

TL;DR: In this paper, the average diameter of L12 precipitates increases from ∼6-nm to ∼50-nm when the solution annealed specimens are aged at 800-°C for 1-h-100h.

TL;DR: In this paper, the authors investigated fatigue crack nucleation in a powder metallurgy produced nickel alloy containing a non-metallic inclusion and found that local slip accumulation was a necessary condition for crack formation and that in addition, local stress and density of geometrically necessary dislocations are involved.

TL;DR: In this article, a near-alpha titanium alloy (Ti6242Si) was subjected to low cycle fatigue loading at room temperature, and deformation occurred primarily by planar slip, localized into slip bands in the primary alpha.

TL;DR: In this paper, a dislocation-based crystal plasticity model is employed to predict the heterogeneous distribution of stress, strain and dislocation activity and is coupled to a phase field model for the description of the nucleation, propagation, and growth of { 1 ¯ 012 } tensile twins.

TL;DR: In this paper, the effect of the third stress invariant in the Drucker function is analyzed and calibrated for metals with body-centered cubic (BCC) and face centered cubic (FCC) crystal systems based on the yielding and plastic flow of both crystal plasticity and biaxial tensile experiments.

TL;DR: In this paper, a continuous dynamic recrystallization (CDRX) process during hot deformation of the as-extruded Al-Zn-Cu-Mg alloy (AA7075) is revealed by conducting thermal simulation compression tests combined with electron back scattered diffraction (EBSD) experiments.

TL;DR: In this article, the effects of strain rate sensitivity on mechanical behavior of Mg alloys under a wide range of applied strain rates by using an improved self-consistent polycrystal plasticity model is investigated.

TL;DR: In this paper, a summary of expressions for Nye's tensor in terms of elastic and plastic deformation gradient, and for both small and large deformations, is presented.

TL;DR: In this paper, the deformation mechanism of micro-pillars fabricated from bulk nanolaminated graphene (reduced graphene oxide, RGO)-Al composites was investigated.

TL;DR: In this paper, the strain-hardening and fracture behavior of high manganese austenitic twinning induced plasticity (TWIP) steel at temperatures ranging from 123 to 773 K were investigated.

TL;DR: In this article, a critical shear stress criterion for direct slip transfer across an α/β interface in Ti-6242 has been established by capturing the local slip penetration through the phase boundary using integrated crystal plasticity and discrete dislocation plasticity (DDP) modelling techniques, combined with experimental micro-pillar compression test results.

TL;DR: In this paper, a tensile deformation of cold-rolled and annealed 7Mn steel was investigated under various strain rates and deformation temperatures and the Luders bands appeared in all specimens.

TL;DR: In this paper, the authors investigated the influence of precipitates on twinning mediated plasticity and the development of corresponding hardening models that account for twin-precipitate interactions using molecular dynamics simulations.

TL;DR: In this article, a 3D unrecovered strain-stress-temperature diagram was presented for a medical grade NiTi wire in wide temperature range −100°C - +200°C.

TL;DR: In this paper, a nonlinear kinematic hardening rule is proposed based on the classical decomposed Armstrong and Frederick's description, by incorporating the hardening/softening effect in the back stress.

TL;DR: In this article, micro slip activation and localization in Ti-6Al-4V deformed in tension have been examined quantitatively using high-resolution digital image correlation (DIC), HR-electron backscatter diffraction (EBSD) and crystal plasticity finite element modelling.

TL;DR: In this article, a detailed investigation has been performed on the creep deformation and age hardening during creep ageing of an aluminum-copper alloy AA2219-T4 under various stress levels that lead to elastic or initial plastic deformation.

TL;DR: In this paper, a FeCoNiNb0.5 medium-entropy-alloy nanocomposite was designed, which possesses a high volume fraction (>50%) of a cubic laves phase but shows superb strength and excellent malleability at room temperature.

TL;DR: In this paper, the authors employed a state-of-the-art crystal plasticity spectral method in conjunction with comparable high-fidelity microstructures to study the coupling effect of micro-mechanical (intrinsic) heterogeneities introduced by grain size, morphology, orientation, and intergranular interaction.

TL;DR: In this article, the effect of the orientation of non-recrystallized grains (non-DRX) and the LPSO phase on plasticity in extruded MgY2Zn1 alloy with a bimodal grain structure was studied in-situ using the combination of synchrotron diffraction and acoustic emission techniques during compression tests.

TL;DR: In this article, a micro-mechanics based plastic damage model is proposed for quasi-brittle materials under a large range of compressive stress, where the damage is due to initiation and propagation of micro-cracks while the plastic deformation is directly related to frictional sliding along microcracks.

TL;DR: In this paper, an elastoplastic theory for saturated freezing soils is presented on the basis of thermoporomechanics, where both Eulerian and Lagrangian formulations considering the phase transition between ice crystals and unfrozen water are given for mass conservation, momentum balance, kinetic energy theorem, first and second thermodynamics, and conduction laws for fluid mass and heat.

TL;DR: In this article, the authors investigated dislocation interactions at the crack nucleation site in near-alpha titanium alloy Ti-6242Si subjected to low cycle fatigue and found that dislocation pileups formed at the boundaries between the primary alpha and two-phase regions provided a barrier to slip transfer between primary alpha grains.

TL;DR: In this article, a dislocation-based hardening law within the elasto-plastic self-consistent polycrystal plasticity model was extended to incorporate the latent hardening effects for predicting anisotropic response of polycrystalline face-centered cubic metals.

TL;DR: In this paper, the formation of stress hotspots in polycrystalline materials under uniaxial tensile deformation was investigated by integrating full field crystal plasticity based deformation models and machine learning techniques to gain data driven insights about microstructural properties.

TL;DR: In this article, the authors developed a non-singular theory of three-dimensional dislocation loops in a particular version of Mindlin's anisotropic gradient elasticity with up to six length scale parameters.

TL;DR: Fanning et al. as discussed by the authors performed cyclic deformation experiments on three titanium alloy microstructures to facilitate calibration of two distinct simplified polycrystal plasticity model frameworks, and the model parameters have been estimated for cyclic loading such that the simulated stress-strain response is consistent with experimental results for each of the titanium micro structures investigated.

TL;DR: A thermodynamically consistent phase field approach for crack propagation is presented in this article, which includes the following novel features: scale dependency was included by relating the length scale to the number of cohesive interatomic planes at the crack tip; surface stresses (tension) were introduced by employing some geometrical nonlinearities even in small strain theory.

TL;DR: In this paper, Zhao et al. investigated the evolution of both microstructural and micromechanical fields in polycrystal copper during uniaxial compression at various elevated temperatures using a recently developed model that integrates a fast Fourier transform-based elasto-viscoplastic model and a phase field recrystallization model.

TL;DR: In this paper, a new computational methodology for 3D discrete Dislocation Dynamics (DDD) in barrier-strengthened materials is developed, which combines the discrete 3D DDD framework with the Finite Element Method (FEM) solution of a continuum field equation for the evolution of dispersed barriers.